Griffart Aude, Joly-Monrigal Pauline, Andrin Julien, Lazerges Cyril, Chammas Michel, Coulet Bertrand
Service de chirurgie orthopédique, hôpital de La Cavale Blanche, CHU, boulevard Tanguy-Prigent, 29200 Brest cedex, France.
Service de chirurgie de la main et du membre supérieur, chirurgie des nerfs périphériques, hôpital Lapeyronie, CHU, 371, avenue du doyen Gaston-Giraud, 34000 Montpellier cedex, France.
Orthop Traumatol Surg Res. 2019 Apr;105(2):291-299. doi: 10.1016/j.otsr.2018.11.020. Epub 2019 Feb 8.
Malunion of the proximal humerus is common and variably tolerated. Classifications developed for proximal humerus malunion (PHM) rely on standard radiographs, which underestimate bone fragment displacement and lack accuracy. The clinical tolerance of PHM is subjective, and revision surgery is not always necessary. The primary objective of this study was to assess the reproducibility and relevance of four CT angle measurements for objectively quantifying the morphological disharmony caused by PHM in a control population then in a population with PHM. The secondary objectives were to identify angle cut-offs and to assess the correlations between angle values and the clinical tolerance of PHM.
Objective criteria for assessing proximal humerus malunion can be identified using CT scans.
Four angles were chosen to quantify proximal humerus disharmony: the angles between the humeral head and the glenoid in the coronal plane (HGCo) and axial plane (HGAx), the angle of tuberosity divergence in the axial plane (TDAx), and the centrum collum diaphyseal angle (CCD). The reproducibility of measurements of the four angles on computed tomography (CT) views was evaluated in a control population and in 46 patients with PHM. To this end, the reproducibility of reference slice selection was determined and intra- and interobserver reproducibility of the angle measurements was then assessed. Patients with PHM were divided into two groups based on clinical tolerance to allow testing for disharmony parameters associated with poor clinical tolerance, which was defined as functional impairment and surgical revision.
Slice selection was found to be reproducible. The Bland-Altman plot indicated that the angle measurements in both the controls and the patients were reproducible within ±2 SDs. Intraclass correlation coefficient values ranged from fair to excellent for all angles in both the controls and the patients. The mean TDAx was higher in the patients than in the controls (72.0° vs. 56.1°, P<0.05) and, within the PHM group, was higher in the subgroup with good vs. poor clinical tolerance (75.8° vs. 69.5°, P<0.05). The CCD angle was greater in the controls than in the patients (129.8° [range, 128.3°-131.3°] vs. 125.9° [range, 122.9°-128.9], respectively) and was significantly greater in the PHM subgroup with good vs poor clinical tolerance (131.4° vs. 122.3°, respectively; P=0.007). The HGCo and HGAx angles were significantly greater in the patients than in the controls (HGCo: 66.6° vs. 52.2°, respectively; HGAx: 17.5° vs. 13.3°, respectively, P=0.55).
The measurement method described here provides a quantitative assessment of postfracture disharmony based on four angles, the HGCo, HGAx, and TDAx. Measurement of these four angles on CT images was found to have good intra- and interobserver reproducibility. The angle values were significantly greater in the patients with PHM than in the controls. Within the patient group, the subgroup with poor clinical tolerance had smaller values of the TDAx, CCD, and HGAx angles and a greater value of the HGCo angle.
IV, retrospective observational study.
肱骨近端畸形愈合很常见，其耐受性因人而异。为肱骨近端畸形愈合（PHM）制定的分类方法依赖于标准X线片，这种方法会低估骨块移位情况且缺乏准确性。PHM的临床耐受性是主观的，并非总是需要进行翻修手术。本研究的主要目的是评估四种CT角度测量方法在客观量化PHM导致的形态学不协调方面的可重复性和相关性，首先在对照组中进行，然后在PHM患者群体中进行。次要目的是确定角度截断值，并评估角度值与PHM临床耐受性之间的相关性。
使用CT扫描可以确定评估肱骨近端畸形愈合的客观标准。
选择四个角度来量化肱骨近端的不协调：冠状面（HGCo）和轴位（HGAx）上肱骨头与关节盂之间的角度、轴位上结节分离角度（TDAx）以及中心颈干角（CCD）。在对照组和46例PHM患者中评估了计算机断层扫描（CT）图像上四个角度测量的可重复性。为此，确定了参考切片选择的可重复性，然后评估了角度测量的观察者内和观察者间可重复性。根据临床耐受性将PHM患者分为两组，以测试与临床耐受性差相关的不协调参数，临床耐受性差定义为功能障碍和手术翻修。
发现切片选择具有可重复性。Bland-Altman图表明，对照组和患者组的角度测量在±2个标准差范围内具有可重复性。组内相关系数值在对照组和患者组的所有角度中范围从一般到优秀。患者组的平均TDAx高于对照组（72.0°对56.1°，P<0.05），并且在PHM组中，临床耐受性良好与较差的亚组之间，TDAx也更高（75.8°对69.5°，P<0.05）。对照组的CCD角度大于患者组（分别为129.8°[范围，128.3°-131.3°]对125.9°[范围，122.9°-128.9°]），并且在临床耐受性良好与较差的PHM亚组中，差异显著（分别为131.4°对122.3°；P = 0.007）。患者组的HGCo和HGAx角度显著大于对照组（HGCo：分别为66.6°对52.2°；HGAx：分别为17.5°对13.3°，P = 0.55）。
这里描述的测量方法基于HGCo、HGAx和TDAx这四个角度对骨折后不协调情况进行了定量评估。发现在CT图像上测量这四个角度具有良好的观察者内和观察者间可重复性。PHM患者的角度值显著大于对照组。在患者组中，临床耐受性差的亚组TDAx、CCD和HGAx角度值较小，而HGCo角度值较大。
IV，回顾性观察性研究。
